Dithiocarbamate fungicides, such as mancozeb and maneb, are sprayed on Satsuma mandarin trees 3 or 4 times during the summer to control major diseases, but laboratory experiments using these chemicals have shown negative effects on phytoseiid mites. Here we evaluated the effects of mancozeb and four alternative fungicides—kresoxim-methyl, dithianone, oxine-copper, and copper hydroxide with calcium carbonate—on the occurrences of phytoseiid mites and their prey Panonychus citri（McGregor）（Acari: Tetranychidae）in neonicotinoid-treated Satsuma mandarin fields. As expected from laboratory findings, mancozeb application reduced the overall population of phytoseiid mites, which was mainly composed of Amblyseius eharai Amitai and Swirski（Acari: Phytoseiidae）, and increased the P. citri density. In contrast, the four alternative fungicides did not adversely affect the phytoseiid mite population, and three of these treatments—kresoxim-methyl, dithianone, and oxine-copper—did not increase the P. citri density. From these results, we encourage careful selection of fungicides when the native natural enemy A. eharai is used for the control of P. citri.